Herein, we report on a case of primary torsion of the greater omentum with segmental infarction, which should provide useful information for the preoperative diagnosis of future such cases. Primary torsion of the greater omentum with omental infarction is a rare condition. There are only a few radiological reports of secondary torsion of the greater omentum caused by the hernial sac. During surgical exploration, infarction of the greater omentum was identified, due to the observation of omental torsion without any underlying cause. We describe a patient with characteristic computed tomography (CT) findings of primary omental torsion with segmental infarction, which correlated with the operative and pathologic results.